Toughened-pitch composition.



.srarns ratrnnr ornion.

EMIL L. T/IANI-IAYFEE,OF ST. LOUIS, li IISSOURI.

iniasia.

No Drawing.

To aZZ whom it may concern:

Be it known that I, EMIL L. MANHAYrnn, acitizen of the United States, and resident of St; Louis, Missouri, have invented certain new and useful Improvements in Toughened-Pitch Compositions, of which the :following is a specification.

This invention relates to a composition of matter for roofing, paving and flooring purposes. The same is accomplished by first reducing the pitch toaliquid state, thoroughly agitating the same, and during the process of agitation by applying and mixing the pitch with infusorial earth or kieselguhr of suchquantity and proportion as to cause the pitch, after it has been placed in containers to assume a plastic toughened state.

Heretofore it has been proposed to saturate and cover both sides of a woven or textile fabric or felt cloth with coal tar in which there has been incorporated sufficient in- Iusorial or diatomaceous earth to produce a cement capable of rendering cloth or the like practically fire-proof, for example, it has been proposed to employ 25 parts of in- -l usorial earth and 75 partsor" coal tar, the same being thoroughly mixed together and heated to bring the same to a fluid consistency; The fabric was then drawn through this fluid bath and the excess of the liquid composition forced out of the fabric by pressure rollers. The cloth thus treated was then passed through a so-c"alled dust bath composed of pulverulent intusorial earth, with the result that the same adhered to the treated cloth, and the product was then hung up. As soon as the infusorial dust thus applied had absorbed all the liquid tar that it was capable of, the dust bath was repeated a sufiicient number of times to accomplish the necessary absorption of the liquid tar.

Usually two applications of the dust-bath sufliced. After the cloth had been finished in the manner aforesaid, in order to prepare the same for market it was made up into rolls and during the process of rolling it was sifted with a powder absorbing material, such as diatomaceous earth, soap-- stone, or other suitable material, to prevent the layers from sticking together.

The foregoing cementitious material is not suitable as a substitute for material produced by the process herein described, and

Specification of Letters Eatent.

iOUGHENED-PI'ECIH COM?OSI1ION.

Patented (let. a, rare.

Application filed December 13, 1910. Serial No. 597,163.

such process as described is accordingly disclaimed by me as being intended to be in cluded within the scope of the claims annexed to this specification or hereinafter inserted therein.

W hat I do claim and desire to secure by Letters Patent is, the treatment of pitch, which is a product distinctly difi erent from tar,'and which has a recognized and distinct technical status. Pitch is a residual prodnot of tar being defined as (see Staddard Dictionary, Funk & iVagna'lls, 1909) f-a thick, dense, black or dark-brown substahce obtained by boiling down tar and from the residues of distilled turpentine.

In carrying out my invention 1 preferably proceed as iollowsz-al mass of pitch, by which terinis included the residue of tars and oils, such as coal-tar pitch, oil-tar pitch, pine-tar pitch. candle-tar pitch, asphalt-and the like, is first reduced to a liquid state and thoroughly agitated while simultaneously adding sufiicient infuse-rial earth or kieselguhr in such proportion as, to cause said pitch after it had been removed and placed in-containers and allowed to cool to assume a plastic toughened state, in which condition it is sufficiently hard to be capable of withstanding the natural heat of the suns .rays, for example, it'will possess a melting point approximately 200 F. and yetbe sufiiciently tough and adhesive to retain the gravel partially embedded therein under varying conditions of service. "As a result of-the incorporation of said kieselguhr there with, the said resultant product will be prevented from running under the natural heat of the sun as is the case with ordinary pitches when placed on sloping roots or in clined surfaces, and also the pitch is rendered more fireproof and has ample-adhesive quality. it is moreover suficiently elastic to permit of expansion and contraction without cracking or brealn'ng when sub jected repeatedly to heat or cold;

When the requisite amount of kieselguhr ,in accordance with the above requlrement 1s added to coal tar pitch, an amount for 91- ample from 15' 'to 20% is amply sufficient,

the melting point of the same which would ordinarily be about 140 F. will be elevated to approximately 200 F., yet at the same time substantially all of the elasticity and low melting point will be preserved.

' nary pitches results in the absorption and retention of the liquid portions, such as any of the light oils, or other tar oils including heavy green oils thereof remaining unvolatilized during the distillation process in the manufacture of such pitches. In addition to this the kieselguhr i. e. infusorial earth appears to act as an insulator against heat and cold. As a result of this absorption of the light oils, the finished product is apparently incapable of ultimately setting to a brittle mass, as is customary with untreated pitches, with the result that the mass is permanently maintained in a plastic state and cracking or running due to cold or heat, is prevented as aforesaid.

The effect of the kieselguhr upon the pitch appears to be due partly to a chemical transformation which may be best explained on the theory, that partial oxidation of the anthracene to anthroquinone occurs, since the melting point of the former is about 210 C. and the latter about 280 C. A13

parently the kieselguhr in such a case serves as a catalytic agent during said agitation and heating of the melted pitch results inthe rapid oxidation of the same and consequent elevation of the melting point. Upon analysis for example, of untreated pitch an amount approximately 7% of crude anthracene was obtained, whereas upon analysis of the fraction obtained from the driedpitch anamount up to 11% of crude anthraquinone containing traces of naphthalene possibly naphthaquinone Was found.

The treatment of coal tar as distinguished from coal tar pitch in the identical manner as above described, does not produce a combination which can satisfactorily be em ployed as a substitute for the product produced by applicant, for the reason that coal tar which is recognized as being an en.- tirely distinct article commercially from coal tar pitch, contains too large a proportion of light oils to permit of the necessary absorption of the same by areasonable proportion of kieselguhr. The only way in which these oils can be taken care of is by some such process as that herein referred to as known in the prior art. This however is entirely unsatisfactory and has never been commercially employed because of its impracticability. In fact it is impossible Whether employing applicants invention or the process herein described as known to the prior art, to directly add kieselguhr to coal tar, as such, and obtain a product which has a high melting point and a lOW freezing point, and which is sufficiently resistant to the change in temperaturesiand sufficiently tough and elastic to permit-of Walking thereon Without damaging efiect crease in the melting point relatively heavy due to puncturing of the layers thereof, and possess the other desirable properties herein described to a suflicient degree to render the same suitable for.roofing and like purposes. lit is obvious that any pitch containing kieselguhr whether the same is obtained by direct addition of the kieselguhr to the pitch or by addition to the tars during distillation thereof from which pitch is produced, is equally Within the scope of my invention, but I distinctly disclaim on the other hand an end product consisting of undistilled tar which as is well known is permanently in a liquid condition, having incorporated therein a small or large amount of kieselguhr or like material. direct heat of the suns rays being in many cases approximately 150 F. that the inof this treatment will be at least in substantial excess of the normal melting point of pitch of 140 F.

The essential feature of my invention is the intermingling of'infusorial earth or hisselg'uhr with pitch in such quantities and proportions as to render the finished product plastic.

By the Word pitch referred to in the above is meant the residue of tars and oils, such as coal tar pitch, oil tar pitch, pine tar pitch, cannel tar pitch, asphalt pitch and the like.

its kaolin, clay and like inert relatively heavy inorganic silicious substances are incapable of substitution for i the inert absorptive materials of lower specific gravity which are capable of remaining substantially in permanent suspension in pitch herein referred to the same are hereby specifically disclaimed as being Without the scope and spirit of my invention as embodied in the accompanying claims.

Kieselguhr or infusorial earth is essentially different from kaolin, clay and like inorganic fillers and therefore its effect upon pitch is likewise quite dissimilar from such heavy fillers.

The following tabulated properties serve to emphasize the essential differences between infusorial earth or kieselguhr and such heavy fillers as clay, kaolin and the like, both alone and mixed With commercial pitch, (Table 1) giving the absorption, loose weight and specific gravity of the materials themselves ;and (Table 2) giving the melting point, slide and settling values of mixtures of kaolin-pitch and kieselguhr-pitch, respectively.

It is obvious that since the It is evident from the foregoing that whereas infusorial earth or kaolin changes the properties of commercial pitch to a very considerable extent, when incorporated therewith in relatively small proportions,

for example 15%,) to wit, the melting point is increased from 126? F. to 159 F. and the slide is decreased from 3.88 to less than 1 inch, and there is practic'all no settling of said kieselguhr even after our hours. On

the other hand, kaolin in similar amounts has no material effect whatsoever upon the properties of the pitch, the melting point being changed not over 3 and the slide being decreased but a few per cent., to wit, about 25% as distinguished from over 85% in the case of kieselguhr and the settling beingover 33% as distinguished from practically nil in the case of kieselguhr. Likewise as fully set forth in Table l the absorptive properties, loose weight and specific gravities of kieselgu'hr and kaolin are materially different.

Having thus fully described my invention, what I claim as new and desire to have secured to me by the grant of Letters Patent, 1s:

- 1. A composition of matter consisting of pitch having suflicient infusorial earth homogeneously incorporated therein. to maintain the same plastic at normal temperatures and to increase the melting point thereof substantially in excess of the melting point of untreated pitch of a similar nature to the pitch therein contained.

2. A composition of matter consisting of pitch having sufiicient kieselguhr homogeneously incorporated therein to render the same plastic at normal temperatures and to lncrease the melting point thereof substantially in excess of the melting point of untreated pitch of a similar nature to the pitch therein contained, and sufiicient to resist, after the initial hardening of the same, the natural heat of the suns rays Without melting. j

3. A composition of matter consisting of pitch having suflicient quantities of inert absorptive material homogeneously incorporated therewith to maintain the same plas tic throughout a materially increased range of temperature, and to increase the melting point thereof substantially in excess of the melting point of'untreated pitch of a similar nature to the pitch therein contained, said inert absorptive material being characterized by a specific gravity not exceeding 2.00, an absorptive property of at least 1 cc. of oresyllc acid per gram, a loose weightnot exceeding 25 lbs. per cubic foot, being capable of increasing the melting point of ordinary pitch when incorporated therewith in amounts of 15% by at least 20 F., andbeingcapableof remaining in suspension in said pitch without more than 15% settling at 85- to 90 C. during an interval of. four hours.

A. A composition of matter consisting of pitch having sufficient quantities of inert absorptive -material homogeneously incorporated therewith to maintain the same plastic throughout a materially increased range of temperature, and to increase the'melting point thereof substantially in excess of the melting point of untreated pitch of a similar nature to the pitch therein contained, said inert absorptive material being characterized by a specific gravity not exceeding 1.8, an.

absorptive property of at least cc. of cresylic acid per gram, a loose we1 ht not exceeding 45 lbs. per cubic foot, being ca pable of increasing the melting point of ordinary pitch when incorporated therewith in amounts of 15% by at least 25 Fwand being capable of remaining in suspension in said pitch without more than 10% settling at 85 to'90 C. during an interval of four hours. 1

5.: A composition of matter consisting of pitch having suflicient quantities of inert absorptive material. homogeneously incorporated therewith to maintain the same plastic throughout a materially increased range of temperature, and to increase the melting point thereof substantially in excess of the melting point of untreated pitch of a similar nature to the pitch therein contained, said inert absorptive material being characterized by a specific gravity exceeding 1.0 and not exceeding 1.8, an absorptive property of at least 1' cc. of cresylic acid per gram, a loose 20 F. and being capable f remaining in suspension in said pitch without more than 15% settling at 85 to 90 C. during an interval of four hours. is

In testimony whereof, I have signed my name to this specification, in presence of two subscribing witnesses. .EMIL L. MANHAYFER. Witnesses:

ALFRED A. Enroo, WALTER C. STEIN. 

